检索结果-南通市图书馆

nitrogen-doped carbon dots as photocatalysts for organic synthesis:Effect of nitrogen content on catalytic activity

Nano Research 2024年第6期17卷 4825-4833页

作者： Kai-Kai Niu Chao-Qun Ma Rui-Zhi Dong Hui Liu Sheng-Sheng Yu Ling-Bao Xing School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China

Regulating the doping of carbon dots(CDs)and the generation of reactive oxygen species(ROS)is essential to selectively control their application in photocatalytic organic reactions.This study successfully synthesized five newly developed nitrogen-doped carbon dots(CDs 1-5)with varying nitrogen content,which have the ability to generate ROS when exposed to light radiation,specifically superoxide anion radicals(O_(2)•-)and singlet oxygen(^(1)O_(2)).The utilization of the aforementioned nitrogen-doped CDs as photocatalysts enables the realization of their potential in facilitating efficient photocatalytic organic conversion.Simultaneously,it was observed that the photocatalytic efficiency exhibited a gradual decrease when the nitrogen content in the CDs increased.In order to provide more evidence for this claim,we employed a set of five CDs in the context of photocatalytic dehalogenation ofα-bromoacetophenone,photocatalytic oxidative coupling reaction of amines to imines,photooxidation reaction of sulfides to sulfoxides,and cross-dehydrogenation coupling(CDC)reaction,in which it was further observed that there was a steady decrease in the yields of photocatalytic organic reactions as the nitrogen content in CDs increased.Notably,CDs 1 exhibited the best photocatalytic efficiency,thereby reinforcing the hypothesis that a higher nitrogen content corresponds to a decreased catalytic efficiency.This study not only investigates the impact of the nitrogen content on the catalytic performance of CDs,but also offers valuable insights for the future utilization of CDs for photocatalytic organic reactions in water.

关键词： carbon dots nitrogen-doped reactive oxygen species photocatalysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Size-controllable synthesis of monodispersed nitrogen-doped carbon nanospheres from polydopamine for high-rate supercapacitors

引用

Frontiers of Chemical Science and Engineering 2023年第11期17卷 1788-1800页

作者： Ning Zhang Fu-Cheng Gao Hong Liu Feng-Yun Wang Ru-Liang Zhang Qing Yu Lei Liu School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China College of Physics and State Key Laboratory of Bio Fibers and Eco Textiles Qingdao UniversityQingdao 266071China

Monodispersed nitrogen-doped carbon nanospheres with tunable particle size(100-230 nm)were synthesized via self-polymerization of biochemical dopamine in the presence of hexamethylenetetramine as a buffer and F127 as a size controlling agent.Hexamethylenetetramine can mildly release NH3,which in turn initiates the polymerization reaction of dopamine.The carbon nanospheres obtained exhibited a significant energy storage capability of 265 F·g^(-1)at 0.5 A·g^(-1)and high-rate performance of 82%in 6 mol·L^(-1)KOH(20 A·g^(-1)),which could be attributed to the presence of abundant micromesoporous structure,doped nitrogen functional groups and the small particle size.Moreover,the fabricated symmetric supercapacitor device displayed a high stability of 94%after 5000 cycles,revealing the considerable potential of carbon nanospheres as electrode materials for energy storage.

关键词： carbon nanospheres size-controlled nitrogen-doped high-rate supercapacitors

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

doped-nitrogen enhanced the performance of Nb_(2)CT_(x)on the electrocatalytic synthesis of H_(2)O_(2)

引用

Nano Research 2023年第5期16卷 6120-6127页

作者： Shijie Zhang Jingnan Zheng Junming Lin Yuanan Li Zhikang Bao Xiaoge Peng Wenkai Ji Lei Ding Zaixiang Xu Guoliang Wang Xing Zhong Jianguo Wang Institute of Industrial Catalysis State Key Laboratory Breeding Base of Green-Chemical Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014China Zhejiang Center for Disease Control and Prevention Hangzhou 310051China

Electrochemical oxygen reduction reaction(ORR)for preparing hydrogen peroxide(H_(2)O_(2))is a promising way to replace the anthraquinone method.The key to H_(2)O_(2)production is the development of catalysts to regulate the oxygen reduction reaction pathway.Here,nitrogen-doped Nb_(2)CT_(x)was prepared by NH3 annealing method.Compared with precursor Nb_(2)AlC(67.01%)and pure Nb_(2)CT_(x)(75.70%),nitrogen-doped Nb_(2)CT_(x)exhibited excellent performance for 2e−ORR with>90%H_(2)O_(2)selectivity(at 0.4 V vs.reversible hydrogen electrode(RHE)).Faradic efficiency of nitrogen-doped Nb_(2)CT_(x)reached 80.75%,whereas those for Nb2AlC and Nb_(2)CT_(x)were 60.35%and 39.27%,respectively.A desirable catalytic stability for 50 h was observed.Density functional theory(DFT)calculations indicated excellent activity of the nitrogen-doped Nb_(2)CT_(x)was attributed to the introduction of N.This excellent activity was conducive to the adsorption of oxygen and promoted the formation of the OOH intermediate.This work can serve as an important reference for regulating the electronic structure of MXene to expand the application area in the electrochemical field.

关键词： Nb_(2)CT_(x) nitrogen-doped electrocatalysis oxygen reduction reaction hydrogen peroxide

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Homogeneous nitrogen-doped(111)-type layered Sr5Nb4O15-xNx as a visible-light-responsive photocatalyst for water oxidation

引用

Nano Research 2022年第12期15卷 9976-9984页

作者： Shiwen Du Hai Zou Yunfeng Bao Yu Qi Xueshang Xin Shuowen Wang Zhaochi Feng Fuxiang Zhang State Key Laboratory of Catalysis Collaborative Innovation Center of Chemistry for Energy Materials(iChEM)Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China University of Chinese Academy of Sciences Beijing100049China

The development of visible-light-responsive photocatalysts for promoting solar-driven oxygen(O2)production from water splitting is a potentially attractive but still a challenging scheme.In the present work,a(111)-type layered perovskite oxynitride,Sr5Nb4O15-xNx,was synthesized via the nitridation treatment of the disk-like oxide precursor under the ammonia flow,which was fabricated using a flux method.The homogeneous dispersion of nitrogen(N)dopant in N-doped Sr5Nb4O15 was ascertained by energy-dispersive X-ray spectroscopy characterization,and the Sr5Nb4O15-xNx was found to be a direct semiconductor with a light absorption edge of approximately 640 nm.Density functional theory investigation implies that the hybridization between the outmost N 2p orbitals and O 2p orbitals upshifts the original valence band maximum of Sr5Nb4O15 and endows its visible-light-responsive characteristics.Loading with cobalt oxide(CoOx)as cocatalyst,the as-prepared Sr5Nb4O15-xNx exhibited an enhanced photocatalytic O2 evolution activity from water splitting under visible-light illumination(λ>420 nm).Moreover,another homogeneous N-doped layered perovskite-type niobium(Nb)-based oxynitride,Ba5Nb4O15-xNx,was also developed and investigated for the visible-light-actuated O2 production,highlighting the versatility of the present approach for exploring novel visible-light-responsive photocatalysts.

关键词： nitrogen-doped visible-light-responsive layered perovskite oxygen(O2)evolution water splitting

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

nitrogen-doped TiO_(2)/Graphene Composites Synthesized via the Vapour-thermal Method

引用

Journal of Wuhan University of Technology(Materials Science) 2022年第6期37卷 1105-1113页

作者：唐海龙王敏 JU Tangtong DAI Yue WANG Meiling MA Yongqing ZHENG Ganhong School of Materials Science and Engineering Anhui UniversityHefei 230039China School of Physics and Optoelectronic Engineering Anhui UniversityHefei 230039China Institute of Physical Science and Information Technology Anhui UniversityHefei 230039China

TiO_(2)/graphene composite was synthesized in the vapor environment of isopropanol.In order to improve the properties of composite,N-doped of TiO_(2)/graphene with different N/Ti molar ratio was prepared in the vapor environment of deionized water and used urea as the source of nitrogen.The N-doped occupies in the interstitial sites of TiO_(2) lattice,substitutes for O element in TiO_(2) and for C element in graphene,and simultaneously changes the chemical states of Ti and O elements in TiO_(2).N-doped changes the morphology of TiO_(2) from nano-sheets to nanoparticles,accompanying with the decrease in specific surface area of the composites,first increases the particle size of TiO_(2) and then decreases,and alters the vibration modes of Ti-OTi.The composite with RN/Ti=2 exhibits the enhanced photocatalytic degradation performance to methylene blue,and the degradation rate increases from 7.7×10^(−2) min^(−1) for the undoped composite to 9.6×10^(−2) min^(−1).

关键词： TiO_(2)/graphene vapor-thermal nitrogen-doped photocatalytic performance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Enhanced Potassium‑Ion Storage of the 3D Carbon Superstructure by Manipulating the nitrogen‑doped Species and Morphology

引用

Nano-Micro Letters 2021年第1期13卷 1-14页

作者： Yanhua Li Kui Xiao Cong Huang Jin Wang Ming Gao Aiping Hu Qunli Tang Binbin Fan Yali Xu Xiaohua Chen College of Materials Science and Engineering Hunan UniversityChangsha 410082People’s Republic of China College of Materials and Chemistry Engineering Hunan Institute of TechnologyHengyang 421002People’s Republic of China Zhuzhou Times New Material Technology Co. LTDZhuzhou 412007People’s Republic of China

Potassium-ion batteries(PIBs)are attractive for gridscale energy storage due to the abundant potassium resource and high energy density.The key to achieving high-performance and large-scale energy storage technology lies in seeking eco-efficient synthetic processes to the design of suitable anode materials.Herein,a spherical sponge-like carbon superstructure(NCS)assembled by 2D nanosheets is rationally and efficiently designed for K+storage.The optimized NCS electrode exhibits an outstanding rate capability,high reversible specific capacity(250 mAh g^(−1) at 200 mA g^(−1) after 300 cycles),and promising cycling performance(205 mAh g^(−1) at 1000 mA g^(−1) after 2000 cycles).The superior performance can be attributed to the unique robust spherical structure and 3D electrical transfer network together with nitrogen-rich nanosheets.Moreover,the regulation of the nitrogen doping types and morphology of NCS-5 is also discussed in detail based on the experiments results and density functional theory calculations.This strategy for manipulating the structure and properties of 3D materials is expected to meet the grand challenges for advanced carbon materials as high-performance PIB anodes in practical applications.

关键词： Polyimide nitrogen-doped Potassium-ion battery 3D carbon material

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Synthesis of nitrogen-doped carbon nanotubes-FePO_4 composite from phosphate residue and its application as effective Fenton-like catalyst for dye degradation

引用

Journal of Environmental Sciences 2019年第2期31卷 188-198页

作者： Lianmei Wei Yi Zhang Shengwen Chen Luping Zhu Xiaoyu Liu Lingxue Kong Lijun Wang School of Environmental and Materials Engineering Shanghai Polytechnic University Research Center of Resource Recycling Science and Engineering Shanghai Polytechnic University Institute for Frontier Materials Deakin University

Phosphate residue is regarded as a hazardous waste, which could potentially create significant environmental and health problems if it is not properly treated and disposed of. In this study, nitrogen-doped carbon nanotubes-FePO_4(NCNTs-FePO_4) composite was successfully synthesized from phosphate residue, and its application as an effective catalyst was explored. Firstly, an effective method was developed to recover FePO_4 from phosphate residue, achieving an impressive FePO_4 mass recovery rate of 98.14%. Then, the NCNTsFePO_4 catalyst was synthesized from the recovered FePO_4 by two main reactions, including surface modification and chemical vapor deposition. Finally, the synthesized NCNTs-FePO_4 was applied to photo-degrade 15 mg/L Rhodamine B(RhB) in a Fenton-like system. The results showed that 98.9% of RhB could be degraded in 60 min, closely following the pseudofirst-order kinetics model. It was found that even after six consecutive cycles, NCNTs-FePO_4 still retained a high catalytic capacity(>50%). Moreover, ·OH radicals participating in the RhB degradation process were evidenced using quenching experiments and electron paramagnetic resonance analysis, and a rational mechanism was proposed. It was demonstrated that the materials synthesized from hazardous phosphate residue can be used as an effective catalyst for dye removal.

关键词： Phosphate residue Fenton-like nitrogen-doped carbon nanotubes-FePO4 Hydroxyl radical

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Preparation of nitrogen-doped titania and its photocatalytic activity

引用

Rare Metals 2007年第3期26卷 254-262页

作者： QIN Haoli GU Guobang LIU Song College of Chemistry South China University of Technology Guangzhou 510640 China School of Science Guizhou Normal University Guiyang 550001 China

Yellowish nitrogen-doped titania was produced through sol-gel method in mild condition, with the elemental nitrogen derived from aqua ammonia. The titania catalysts were characterized using XRD, BET, TEM, XPS, and UV-Vis diffuse reflectance spectrophotometer, and their photocatalytic activities were evaluated under UV and visible light, respec tively. The XRD results showed that all titania catalysts were anatase. More significantly, the crystallite size of nitrogen-doped titania increased with an increase in N/Ti proportion, and the doping of nitrogen could extend the absorption shoulder into the visible-light region, thus it possessed a higher visible-light activity illustrated by decolorization of methyl orange （65.3%） under the irradiation of visible light, whereas pure titania showed little of such kind of visible light activity. The UV-light activity of nitrogen-doped titania catalysts was worse than that of pure titania and Degussa P25. In the range of N/Ti proportion of 4-10 mol%, the activity of nitrogen-doped titania weakened appreciably in the visible-light region as the N/Ti proportion increased, whereas a reverse relationship existed under the irradiation of UV light.

关键词： photocatalysts titania nitrogen-doped methyl orange

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Electrocatalytic water splitting at nitrogen-doped carbon layers-encapsulated nickel cobalt selenide

引用

Journal of Energy Chemistry 2019年第7期28卷 161-170页

作者： Chuanlai Jiao Xiangjie Bo Ming Zhou Key Laboratory of Nanobiosensing and Nanobioanalysis at Universities of Jilin Province Key Laboratory of Polyoxometalate Science of Ministry of EducationNational & Local United Engineering Laboratory for Power Batteries Department of Chemistry Northeast Normal University

Generally,the catalytic overpotentials of hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)are unavoidable because of the low charge transfer.In this work,two strategies of alloying of Co with Ni and enclosing of electrocatalysts with carbonaceous materials were both used to accelerate the catalytic efficiency of cobalt selenide for water splitting.The nitrogen-doped carbon(NC)layer improves the reaction kinetics by efficient charge transfer.The alloying of metal into composited electrocatalysts can modify the electronic properties of host materials,thereby tuning the adsorption behavior of intermediate and improving the electrocatalytic activity.As expected,Nyquist plots reveal that the charge-transfer resistance(Rct)of nickel cobalt selenide encapsulated into nitrogen-doped carbon layer(CoNiSe/NC-3,Co:Ni=1:1)are just 5 and 9 for HER and OER,respectively,which are much lower than those of CoSe/NC-1(Co:Ni=1:0)(81 and 138)and CoNiSe/NC-3 without NC(CoNiSe-3)(54 and 25).With the high charge transfer and porous structure,CoNiSe/NC-3 shows good performance for both HER and OER.When current density reaches 10 m A cm-2,only 100 and 270 mV overpotentials are required for HER and OER,respectively.With the potential of 1.65 V,full water splitting also can be catalyzed by Co Ni Se/NC-3 with current density of 20 m A cm-2,suggesting that CoNiSe/NC-3 could be used as replacement for noble metal electrocatalysts.

关键词： Nickel cobalt selenide nitrogen-doped carbon layer Water splitting Hydrogen evolution reaction Oxygen evolution reaction

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

nitrogen-doped hierarchical porous carbon from polyaniline/silica self-aggregates for supercapacitor

引用

Chinese Journal of Chemical Engineering 2019年第3期27卷 709-716页

作者： Peipei Li Dazhi Zhang Yunhui Xu Caihua Ni Gang Shi Xinxin Sang Key Laboratory of Synthetic and Biological Colloids Ministry of Education School of Chemical and Material Engineering Jiangnan University Xuzhou College of Industrial Technology

In this paper, nitrogen-doped hierarchical porous carbon(N-HPC) was prepared from polyaniline(PANI)/silica self-aggregates. H-bonding between N\\H groups in aniline/PANI and \\OH groups in nano silica template led to a self-assembly type, which enabled the formation of uniform N-HPC nanoparticles. Silica self-aggregates provided macroporous channels resulted in a decreased diffusion distance. After removing the hard template,the N-HPC had a high surface area(899 m^2·g^(-1)). Owing to two co-existed synergetic energy-storage mechanisms and the hierarchical porous structure, the obtained N-HPC exhibited a high specific capacitance of 218.75 F·g^(-1) at 0.5 A·g^(-1), compared with the nonporous nitrogen-doped carbon(N-C) derived from pure PANI. Moreover, the N-HPC electrode demonstrated excellent cycle life, retaining 99% of its initial specific capacitance after 1000 cycles.

关键词： nitrogen-doped Hierarchical porous carbon Hard template Silica self-aggregates

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：